1. Field of the Invention
This invention relates to rotary torquemeters, and in particular, to rotary torquemeters utilizing foil-type strain gauges.
2. Description of the Prior Art
In U.S. Pat. No. RE.26,501, issued to Sydney Himmelstein et al, and owned by the assignee hereof, a rotary transformer is illustrated for use in providing electrical signals from a rotating member. In the subsequent U.S. Pat. No. 3,531,748, of Richard S. Tveter et al and U.S. Pat. No. 3,717,029 of Richard S. Tveter, each of which patents is also owned by the assignee hereof, rotary torquemeters are disclosed utilizing such a rotary transformer in conjunction with a strain gauge. As shown in the wiring diagram of said Tveter et al U.S. Pat. No. 3,531,748, the rotary torquemeter utilizes a pair of such rotary transformers in transmitting a signal from an oscillator supply through the strain gauge carried on the rotating member to an output rotary transformer which is connected to a suitable signal receiving means for indicating or recording the output signal indicating the torque being transmitted through the rotary member.
In said Tveter U.S. Pat. No. 3,717,029, the torquemeter is disclosed as including a high performance wide band rotary transformer eliminating the need for resonant circuits and effectively precluding spurious signals being generated in the torquemeter control. As indicated in said torquemeter patents, the prior art teaches a number of different forms of torquemeter structures and includes the following U.S. Pat. Nos. 1,394,901 (Hobart); 2,283,942 (Morris); 2,894,231 (Krasno); 2,445,427 (Godsey, Jr.); 2,531,228 (Macgeorge); 2,548,397 (Schaevitz); 3,179,909 (Cheney); 3,317,873 (Himmelstein); 3,317,874 (Honsinger); and 3,348,181 (Stromswold).
Also included in the prior art as indicated in the above discussed patents, are the following foreign patents: Australia; Pat. No. 268,842 Canada; Pat No. 453,819 and Great Britain Pat. No. 784,733.